The present invention relates to an apparatus for feeding and loading individual bags formed in a continuous strip in which successive bags are connected end to end. More specifically, the present invention relates to an apparatus that includes an integrated printer assembly that prints a label or product marking on each of the bags in a continuous strip immediately prior to the printed bag being loaded with the product being packaged.
Currently, many manufacturers utilize automated loading machines to load products to be packaged into individual plastic bags. The plastic bags are typically contained in a xe2x80x9cwicketxe2x80x9d in which successive bags are stacked on top of each other and held in alignment by a header having a series of wicket rods. Once each bag is filled with the product to be packaged, the bag is torn along a line of perforation and separated from the header that aligns the stack of bags. After the bag has been filled with the product, the bag is transferred to a drop sealer in which the two layers of plastic forming the bag are heat sealed in a conventional manner. Although the combination of a wicketed bag loading machine and a drop sealer is in wide use and has proven to be effective, drawbacks exist in the use of plastic bags stacked in the wicket package.
One such drawback is the limitation in the type of printing that can be applied to the individual bags in the wicket. Since the bags in the wicket are stacked on top of each other and are loaded with a product while still attached to the wicket header, there is no possibility of printing a design on the plastic bag prior to the insertion of the product. Although the wicketed bags could be printed prior to assembly into the wicketed packet, the manufacturer of the wicketed bags typically mass produces the bags without customizing the bags for the individual customer. Thus, if the customer wishes to imprint information on the bags after purchase from the manufacturer, the wicketed bags must be imprinted after the product has been loaded and the wicketed bag sealed by the drop sealer. If the product being sold in the sealed plastic bags includes an irregular surface, printing after the bag has been filled can prove to be a difficult and imprecise proposition.
Recently, continuous strips of bags that are end connected have become available for use in packaging products. Each of the bags in the continuous strip includes an open end that is connected to the closed end of the next bag in the continuous strip. Rolls of continuous strip bags can include at least 1000 bags. However, the automated feeding and loading of the continuous strip of bags has also presented problems in the feeding of the bags from the supply source and the opening of the bags in the continuous strip prior to loading of the products to be packaged.
In currently available packaging apparatus that open and load continuous strips of bags that are end connected, the printing on each bag is done by a printer that is typically located upstream from the location at which the printed bag is loaded with the product being packaged. Although an upstream printer is adequate when loading identical products into bags such that the printing on each individual bag does not have to correspond to the particular product being packaged, drawbacks exist if the bag feeding and loading apparatus is used to package products that are specialized and require specific labeling for the product being packaged. For example, if the bag feeding and loading apparatus is used to package medical prescriptions for individual patients, it is critical that the information printed upon each individual bag matches the product being placed within the bag. In a feeding and loading apparatus in which several cycles of the apparatus take place between the printing of an individual bag and the loading of the same bag, an opportunity exists for misalignment between the printed product packaging and the actual product being inserted therein.
In addition to the possible misidentification that can occur due to the number of bags positioned between the bag being loaded and the bag being printed, the printed bags extending between the loading area and the printing area result in wasted product during changeovers from bag types or the type of printing being placed upon the bag. In many cases, as many as four to six bags can be wasted during each changeover.
Therefore, it is an object of the present invention to provide an apparatus that can be used to print, feed and load individual bags with increased accuracy. Further, it is an object of the present invention to provide such an apparatus that feeds an article into the bag immediately following the printing of the bag by the integrated printing assembly. Further, it is an object of the present invention to position the printing assembly immediately adjacent to the loading location for the bag, such that the loading and printing occurs in the same cycles of the apparatus to improve the accuracy between the printed information and the product and decrease product loss.
The present invention is an device for feeding, printing and loading a bag from a continuous strip of bags with a desired product to be packaged. The apparatus of the present invention is particularly desirable in loading individualized products into successive bags where each of the bags must be individually printed with information specifically related to the product being placed within the bag.
The device of the present invention includes a feed assembly that feeds a continuous supply of bags from a supply source. If the supply source is a roll of bags, the feed assembly includes a series of dancers that maintain tension in the strip. Alternatively, if the continuous strip of bags are formed as a fan-folded supply, the feed assembly includes a vacuum tensioning roll that ensures that the fan-folded continuous strip of bags is fed to the remaining components of the apparatus under tension.
A printer assembly is positioned adjacent to the feed assembly to receive the continuous strip of bags to be loaded. The printer assembly is operable to print various types of indicia or information on the individual bags of the continuous strip. The printer assembly receives control and printing information from a control unit such that the printer assembly can be operated to print different types of information on successive bags of the continuous strip.
Positioned immediately downstream from the printer assembly is a loading assembly. The loading assembly receives the bag that has just been printed by the printer assembly and opens the bag such that a product can be placed into the bag. The loading assembly is positioned immediately adjacent to the printer assembly such that the last bag that was printed by the printer assembly is immediately loaded with the product being packaged. In this manner, no individual bags are positioned between the bag currently being loaded and the bag currently being printed. Thus, the apparatus of the present invention ensures that each individual bag is loaded with product immediately after the individual bag has been printed.
After the individual bag has been printed and loaded by the apparatus of the invention, the bag is separated from the continuous strip and sealed in a downstream process.
As discussed above, the apparatus of the present invention is capable of printing and loading each pre-opened bag during one cycle of the device operation. In this manner, the device ensures that the contents of the package will match the information printed on the bag.
Various other features, objects and advantages of the invention will be made apparent from the following description taken together with the drawings.